Cigarette smoke boosts Alzheimer's risk

A study led by Rusanen M. from University of Eastern Finland and colleagues from other organizations suggests cigarette smoking may boost risk of Alzheimer's disease and vascular disease several decades later.

The study, which was published online on Oct 25, 2010 in Archives of Internal Medicine, showed men and women who smoked more than 2 packs a day were twice as likely as those who did not to develop dementia, 2.57 times as likely to have Alzheimer's disease and 2.7 times as likely to develop vascular disease.

Vascular disease includes any condition that affects the circulation system such as peripheral artery disease, aneurysm, renal artery disease, Raynaud's phenomenon, Buerger's disease, peripheral venous disease, varicose veins, venous blood clots, blood clotting disorders, and lymphedema, according to Cleveland Clinic, which has nothing to do with the current study.

For the study, Rusanen et al. analyzed data from a multi-ethnic population-based cohort of 21,123 members of a heath care system who participated in a survey in 1978 and 1985. Diagnose of dementia, Alzheimer's disease, and vascular disease were made in internal medicine, neurology, and neuropsychology between Jan 1, 1994 and July 31, 2008.

During a 23-year follow-up, 5367 people were diagnosed with having dementia including 1136 cases of Alzheimer's disease and 416 cases of vascular disease.

They concluded "heavy (cigarette) smoking in midlife was associated with a greater than 100% increase in risk of dementia, AD, and VaD more than 2 decades later. These results suggest that the brain is not immune to long-term consequences of heavy smoking."